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1.
新疆某枢纽工程鱼道的设计   总被引:1,自引:0,他引:1       下载免费PDF全文
新疆某枢纽工程为低水头拦河建筑物,位于河流平原区,两岸地形平坦开阔。11月-翌年3月,泄洪闸全部开启,河道基本为自然状态,鱼类可以自由通过;4-10月,部分泄洪闸关闭,是本工程的过鱼季节。过鱼对象主要是新疆裸重唇鱼等需要短距离迁徙的裂鳆鱼类,兼顾草鱼、鲢等经济鱼类。综合考虑诱鱼能力、过鱼能力、鱼类适应程度、建造成本和运行维护等因素,其过鱼设施经过比选后选定为仿自然通道型鱼道。介绍了该工程仿自然通道型鱼道的论证与设计过程,为低水头拦河建筑物的过鱼设施设计提供借鉴。  相似文献   

2.
常规鱼道的研究和设计大多侧重于其内部结构和水流条件等方面,对鱼道进口位置布置及结构优化的研究相对较少,往往存在鱼类发现并进入鱼道较为困难的情况。通过建立鱼道进口设计的生态水力学指标,提出了某项目集诱鱼进口所需要满足的流速范围为0.47~1.30 m/s,将鱼类游泳能力与鱼道进口流态指标相结合,用标准三维κ-ε模型数值模拟的方式,对以往鱼道进口位置的选择原则进行了验证,提出了一种可控流量、流速的新型诱鱼补水装置,对鱼道进口结构进行优化。该诱鱼补水装置利用局部水流落差,上游发电下泄水流进行诱鱼补水,避免采用自库区压力管道引水而产生的消能问题,降低了鱼道运行的成本;同时降低机组满发或发电流量较高时河段内的流速,可达到灵活调控诱鱼水流进而诱导鱼类进入鱼道完成洄游的效果,最终完成鱼道进口的优化,提高过鱼效果。  相似文献   

3.
鱼道是解决拦河筑坝阻隔鱼类洄游的重要手段之一。为了满足兴建峡江水利枢纽工程后洄游鱼类上溯的要求,保护赣江水生生态环境的完整性,减缓工程对鱼类种群遗传交流的影响,针对峡江水利枢纽实际情况制定了鱼道过鱼方式。鱼道采用垂直竖缝式结构设计,由上游鱼道(出口段)、坝体过鱼孔口、下游主、副鱼道(进口段)、集鱼系统及连接段组成,设计主要过鱼季节为4—7月,流速0.7~1.2 m/s。采用仪器监测与人工观察相结合的方式对峡江鱼道过鱼效果进行了初步监测。监测结果显示:2017年监测到过鱼总数67.8万尾,其中上行占41.67%;期间共监测到22种鱼类,共计4目、7科、18属,以小型鱼类为主,如贝氏■(Hemiculter bleekeri)、三角鲂(Megalobrama terminalis)、银鲴(Xenocypris argentea)、银鮈(Squalidus argentatus);不同季节过鱼数量不同,其中以二季度最多,占总数49.17%,过鱼数量以7月最多;过鱼数量昼夜差别大,以上午10:00至下午16:00是过鱼数量最多;与国内其他鱼道相比,峡江鱼道过鱼数量较多,过鱼效果显著。  相似文献   

4.
连江西牛鱼道运行效果的初步研究   总被引:5,自引:0,他引:5       下载免费PDF全文
鱼道建设被认为是有效缓解水坝阻隔鱼类洄游的重要方法之一,而鱼道效果监测是评价其功能的重要环节。连江西牛鱼道是广东省第一座建立在水坝主体上的过鱼通道,为了解其运行效果,采用张网法和截堵法,2012年3-8月共6次对西牛鱼道的过鱼效果进行监测。研究表明,西牛鱼道共监测到鱼类3目、8科、30属、38种,以银鮈(Squalidus argentatus)、乐山小鳔鮈(Microphysogobio kiatingensis)、子陵吻鰕虎(Rhinogobit giurinus)等小型鱼类为优势类群。进入鱼道的鱼类呈现昼夜差异,上午集鱼效果要显著优于其他时间段;不同季节集鱼的种类和数量呈现较大差别,3-8月集鱼数量逐渐减少,集鱼种类数以5月最多。与国内外其他鱼道的过鱼效果比较,西牛鱼道能较好地发挥其功能。  相似文献   

5.
Santo Antonio过鱼设施位于亚马逊河最大支流玛代拉河下游,其设计规模宏大,在世界范围内鲜有,并且工程建设地所在区域水文环境和鱼类生物学特征等与我国长江较为类似,通过分析该过鱼设施,得出启示主要包括:(1)过鱼设施是为生物对象设计的水利工程,其设计和建设过程中必须由工程师和生物学家紧密合作;(2)吸引水流对过鱼设施的成败起关键性作用,虽然吸引水流系统需要加大投资并且运行过程中会损失大量的水能,但从确保过鱼设施效果而言是非常必要的;(3)物理模型对于鱼道进口位置,鱼道内部水力学特征的确定等具有重要参考价值,尤其在1:1局部模型内开展的生物学实验是细化和优化鱼道内部结构细节的有效方法;(4)卵石框(石笼)隔板的水池分隔方法兼具水池式鱼道与仿自然通道的双重特征,并且完工后还可以根据鱼道的运行情况灵活调整,非常方便;(5)进口处采用较高的人字闸门,即可适应尾水变化,又可与吸引水流系统相配合,创造出有效的吸引水流,一举多得;(6)全部采用大功率灯泡式水轮机是保护下行鱼类的有效措施;(7)监测系统和公众教育等配套设施的建设非常必要,有利于改进鱼道运行方式和提高过鱼效率。  相似文献   

6.
不同位置和朝向的鱼道进口诱鱼效果   总被引:1,自引:1,他引:0  
为了探明不同进口朝向的布置方式和进口位置对诱鱼效果的影响,本研究通过建立鱼道进口概化模型,设计3种环境流速工况,以马口鱼为实验对象,针对不同朝向和不同位置鱼道进口分别进行放鱼实验。结果显示,在同一鱼道进口位置时,垂直于河道水流方向上的鱼道进口其诱鱼效果明显优于顺河道水流方向的鱼道进口;当开启与电站不同相对位置不同的进口时,其诱鱼效果受河道水流速度和进口位置的影响较为显著;在所设计实验工况中,环境流速为0.3 m/s时,鱼道进口诱鱼效果最好。研究结果将对水利工程中鱼道进口布置具有重要的参考意义并指导工程实践。  相似文献   

7.
介绍了湄公河渔业资源概况及其流域下游主要的洄游鱼类,分析了萨拉康水电站阻隔对洄游鱼类造成的影响,确定了上游湄公河洄游系统的主要过鱼对象;根据萨拉康水电站枢纽布置以及所在地的地形地质特征,对可行的鱼道布置方案进行了优选论证,并对右岸方案鱼道进口、鱼道出口、鱼道结构、附属设施等进行了初步设计探讨。  相似文献   

8.
与鱼道设计相关的鱼类游泳行为研究   总被引:12,自引:0,他引:12       下载免费PDF全文
在鱼类生境遭受破坏,渔业资源日益减少的今天,修建鱼道等过鱼设施已成为减缓水利工程建设所致不利影响的重要举措。纵观世界各国,早期的鱼道建设往往因为缺乏对鱼类的了解而最终成为摆设。我国的鱼道建设起步晚,其再度兴起需要更可靠的生物学信息。鱼类的游泳能力及行为关系着鱼道设计的各个方面,决定着设计的成败。文章针对鱼道设计,综述了国内外几十年来鱼类游泳行为的研究成果。鱼类的游泳速度可分为三类,即持续游泳速度,耐久游泳速度和突进游泳速度,其中与鱼道设计密切相关的是后两者。影响鱼类游泳速度的因素既有生物个体因素也有环境因素,主要包括摆尾频率、体长、疲劳时间、温度及耗氧量等。文章最后简述了鱼类行为学在鱼道设计中的应用。我国针对过鱼设施建设的鱼类行为学研究极少,总结国外的研究方法和经验成果可为我国的过鱼设施建设提供生物学基础,促进该领域的发展。  相似文献   

9.
长吻鮠网箱养殖初试   总被引:1,自引:1,他引:0  
试验分两组在2m×1m×1.5m的网箱内进行。经4个月饲养长吻鱼危平均体重达到3818g和3082g,单产81和68kg/m2,饲料系数232和212。在水库网箱养殖中,水温对长吻鱼危的生长及饲料利用影响明显  相似文献   

10.
1993年7月~1997年5月,在夏季采用网袋、网箱开展虾夷马粪海胆F2代稚海胆的海区渡夏,壳径日平均生长量比室内提高33.6%~61.6%;采用网箱平面培育方法进行F2代稚海胆室内中间育成和F3代稚海胆室内中间育成中试,壳径的日平均生长量随时间呈下降趋势,为0.53×10-2~1.46×10-2cm/d,体重日平均生长量呈上升趋势,介于2.32×10-2~10.72×10-2g/d之间,培养中密度过大会降低海胆的成活率并导致疾病发生;采用立体水槽开展陆地工厂化养成,经13个月,海胆壳径由1.16cm增至5.98cm,体重由0.47g增至61.0g,性腺指数达18.0%。  相似文献   

11.
12.
Growth hormone (GH) and reproduction: a review   总被引:5,自引:0,他引:5  
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations.  相似文献   

13.
The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna.  相似文献   

14.
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China.  相似文献   

15.
Protein and amino acid composition of the mantle of juvenile O ctopus vulgaris (Cuvier, 1797) during fasting for 27 days were determined. Average protein content of octopus mantle was of 711.19 ± 46.80 g kg?1 DW, and it decreased with increasing fasting days. The non‐essential amino acids content was higher (486.18 ± 11.08 g kg?1 protein) than essential amino acids (425.82 ± 9.15 g kg?1 protein) at the start of the experiment (unstarved animals). The results suggest that the amino acid profile of the mantle where the most abundant amino acids are Arg, His, Lys, Gly, Leu and Pro could indicate a prolonged fasting condition (>20 days) or poor nutrition of O . vulgaris. This study supports the idea of using mantle for metabolic needs of starved O . vulgaris suggesting that the degradation pathway of amino acids to pyruvate and tricarboxylic acid cycle intermediates was favoured contrary to the degradation pathway of ketogenic amino acids. Special considerations should be taken concerning Thr, Ile, Ser, Ala, Asx (Asp, Asn), Glx (Glu, Gln) (because of their fast intake) and Lys and His (due to their stable contents) during a prolonged period of fasting.  相似文献   

16.
17.
The endemic, anadromous cyprinidChalcalburnus tarichi is the only fish species known to occur in alkaline Lake Van (Eastern Anatolia, Turkey). EightC. tarichi were maintained individually in Lake Van water (17 – 19°C; pH 9.8; 153 mEq·I–1 total alkalinity; 22 total salinity) and tank water samples analyzed for 24 h in 2 to 4 h intervals. At zero time, < 1µM ammonia was present and urea was undetectable in the tank water; at 24 h, total ammonia and urea made up 114±32 and 35±25µM, respectively. Over the experimental period, ammonia-N and urea-N excretion averaged 1041±494 and 607±169moles·kg–1 fish·h–1, respectively. The extent of urea excretion was highly variable between specimens. Uric acid excretion was not detectable.Urea was present at high concentrations in all tissues and plasma (25 – 35moles·g–1·ml–1) of freshly caughtC. tarichi; total ammonia content of the tissues was by a factor of 1.9 (liver) to 3.0 (brain) lower. High arginase activity (2.4±0.2 U·min–1·g–1) was detected in the liver ofC. tarichi but ornithine carbamoylphosphate transferase, a key enzyme of the ornithine-urea-cycle, was absent. Ureagenesis is likely through degradation of arginine and/or uricolysis. High glutamine synthetase activity (11±0.6 U·min–1·g–1) and low ammonia content in brain suggest that, like other teleosts,C. tarichi has an efficient ammonia detoxification in the brain, but in no other tissue.Nitrogenous waste excretion at alkaline pH is discussed. The ability ofC. tarichi to excrete high levels of ammonia at extremely alkaline pH is unique among teleosts studied so far. The mechanism of ammonia excretion under Lake Van conditions remains to be elucidated.  相似文献   

18.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg.  相似文献   

19.
  1. Humanity is facing a biodiversity crisis, with freshwater-associated biodiversity in a particularly dire state. Novel ecosystems created through human use of mineral resources, such as gravel pit lakes, can provide substitute habitats for the conservation of freshwater and riparian biodiversity. Many of these artificial ecosystems are subject to a high intensity of recreational use, however, which may limit their biodiversity potential.
  2. The species richness of several taxa (plants, amphibians, dragonflies, damselflies, waterfowl, and songbirds) was assessed and a range of taxonomic biodiversity metrics were compared between gravel pit lakes managed for recreational fisheries (n = 16) and unmanaged reference lakes (n = 10), controlling for non-fishing-related environmental variation.
  3. The average species richness of all the taxa examined was similar among lakes in both lake types and no substantial differences in species composition were found when examining the pooled species inventory. Similarly, there were no differences between lake types in the presence of rare species and in the Simpson diversity index across all of the taxa assessed.
  4. Variation in species richness among lakes was correlated with woody habitat, lake morphology (surface area and steepness), and land use, but was not correlated with the presence of recreational fisheries. Thus, non-fishing-related environmental variables had stronger effects on local species presence than recreational fisheries management or the presence of recreational anglers.
  5. Collectively, no evidence was found that anglers and recreational fisheries management constrain the development of aquatic and riparian biodiversity in gravel pit lakes in the study region; however, the conservation of species diversity in gravel pit lakes could benefit from an increasing reliance on habitat enhancement activities.
  相似文献   

20.
The aim of this study was to describe two epizootics of high mortalities from infection with Streptococcus agalactiae, occurring in captive rays held in a marine display aquarium in south‐east Queensland, Australia, in 2009 and 2010. Five different species of rays were affected, including mangrove whiprays (Himantura granulata), estuary rays (Dasyatis fluviorum), eastern shovelnose rays (Aptychotrema rostrata), white‐spotted eagle rays (Aetobatus narinari) and blue‐spotted mask rays (Neotrygon kuhlii). This report describes the history of both epizootics including collection, quarantine and husbandry of rays, the disease epizootics, clinico‐pathological features of the disease, antimicrobial therapy, autogenous vaccine production, and laboratory studies including clinical and histopathology, bacteriology, PCR, molecular serotyping and sequencing of the bacterium S. agalactiae.  相似文献   

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